KR100919716B1 - Image display element and image display device - Google Patents

Abstract

The present invention is a transmissive stacked holographic optical element constituting an image display device, and a plurality of transmissive holographic optical elements 13, 14, 15 having different diffraction acceptance incident angles are stacked. Each transmission hologram optical element has a different light exit angle with respect to the center incidence angle of each diffraction incident angle at an arbitrary wavelength in the visible region, thereby widening the optical diffraction angle of the incident light and increasing the light utilization efficiency. It is possible to optimally set the distance between the color modulation elements of the optical modulation element in view of the utilization efficiency.

Description

Image display element and image display device

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmissive stacked holographic optical element having a wide screen angle, and moreover, to an image display element and an image display apparatus using the transmissive laminated holographic optical element.

This application claims priority based on Japanese Patent Application No. 2001-335404 for which it applied on October 31, 2001 in Japan. This application is integrated in this application by reference.

2. Description of the Related Art Conventionally, a projection type image display apparatus using a reflective spatial light modulator such as a reflective TN liquid crystal panel has been proposed as shown in FIG. In this image display apparatus, the luminous flux emitted from the lamp light source 107 enters the illumination optical system 108 having functions such as correction of luminous flux cross-sectional shape, uniformity of intensity, divergence angle control, and the like. This illumination optical system 108 has a P-S polarization modulator (not shown). This P-S polarization modulator has a function of equipping a non-polarized light beam with an efficiency of 50% or more in either polarized light of either P-polarized light or S-polarized light.

In the image display apparatus shown here, the light beam passing through the illumination optical system 108 is in a polarized state in which the electric vector oscillates mainly in a direction perpendicular to the surface of FIG. This polarization state is the polarization direction which becomes S polarization | polarized-light with respect to the reflecting surface of the dichroic mirror 109 of red reflection light which enters next. That is, the luminous flux passing through the illumination optical system 108 deflects only the red light component by 90 degrees by the dichroic mirror 109 of the red reflected light. The light beam of the red light component is reflected by the mirror 110 and enters the red polarizing beam splitter (hereinafter referred to as red PBS) 111. In the dielectric film 111a of the red PBS 111, only the S deflection component is reflected, and the incident polarization 112 is incident on the reflective TN liquid crystal panel 113 for red light.

In the red type reflective TN liquid crystal panel 113, the incident light beam modulates and reflects the polarization state corresponding to the display image. The light beam reflected by the red light reflection type TN liquid crystal panel 113 again enters the dielectric film 111a of the red PBS 111. In this dielectric film 111a, since only P-polarized light is detected, polarization modulation is converted into luminance modulation. The emitted light beam thus converted into luminance modulation enters the cross dichroic prism 114.

On the other hand, the light beam which permeate | transmitted the dichroic mirror 109 of red light reflection injects into the dichroic mirror 115 of next green light reflection. Here, only the green light component is reflected, and the remaining blue light component is transmitted. The separated green light and blue light, like the above-mentioned red light, reflect only the S polarization component by the green PBS 116 and the blue PBS 118, respectively, and the green Tref liquid crystal panel 117 and the blue light for green light are reflected. It enters into the reflective TN liquid crystal panel 119, respectively.

The luminous flux reflected by modulating the polarization state by the green light reflection type TN liquid crystal panel 117 and the blue light reflection type TN liquid crystal panel 119 is a dielectric film of the green PBS 116 and the blue PBS 118. Incident on 116a and 118a, where only the P-polarized component is detected to transmit, and polarization modulation is converted into luminance modulation. The blue and green output light beams converted into the luminance modulation are incident on the cross dichroic prism 114, respectively.

Blue light, green light, and blue light incident on the cross dichroic prism 114 are synthesized in the cross dichroic prism 114, and are incident on the projection optical system 120.

The projection optical system 120 forms the incident light beam on the screen 121. On this screen 121, an image is displayed as a predetermined image.

As an illuminating device for a reflective spatial light modulator, there exist some which were described, for example in Unexamined-Japanese-Patent No. 10-48423. The illuminating device described in this publication is a hologram color filter in which two transmissive holographic optical elements are stacked and use the wavelength dispersion of the hologram.

As shown in Fig. 2, the hologram color filter is formed by stacking two holograms 102 and 103 having different wavelength dependences of diffraction efficiency with respect to the illumination light 101 having a predetermined incident angle θ. . In this hologram color filter, the wavelength dependency of the diffraction efficiency is small, and color balance of three colors of R (red), G (green), and B (blue) can be corrected to provide a bright color filter.

In this hologram color filter, the wavelength dependence of the diffraction efficiency of the two holograms 102 and 103 is set such that the spatial wavelength distribution due to wavelength dispersion does not coincide, as shown in FIG. Therefore, the red light diffracted by the hologram 102 on the incident side illuminates the red pixel 104 which is not diffracted by the hologram 103 on the exit side, and the blue light and green light which is not diffracted by the hologram 102 on the incident side emits the light. It is diffracted and spectroscopically by the side hologram 103, and is focused on the corresponding color pixels 105 and 106, respectively.

In addition, as the illuminating device for the reflective spatial light modulator, as shown in Fig. 4, using laminated hologram color filters 124r, 124g, and 124b is disclosed, for example, in Japanese Patent Application Laid-Open No. 9-189809. It is proposed.

In this lighting apparatus, the read light emitted from the illumination light source (not shown) enters the hologram color filters 124r, 124g, and 124b via the coupling prism 126 and the glass substrate 125. These hologram color filters 124r, 124g, and 124b are volume hologram lenses for red, green, and blue, respectively. Such hologram color filters 124r, 124g, and 124b have an interference height attached to them in advance by laser exposure, and have almost the size of one pixel (a group consisting of three color pixels of R, G, and B in total). Each color light microlens having a corresponding area is laminated.

The hologram color filters 124r, 124g, and 124b include the red light component, the green light component, and the blue light component of the spectrum of the read light R _L , the cover glass 123, the common electrode 124, and the alignment layer of the reflective liquid crystal panel. 133, the liquid crystal layer 132, the alignment film 131, and the dielectric mirror film 130 are transmitted, and focused on the corresponding color pixel electrodes 129r, 129g, and 129b on the pixel electrode layer 129, respectively.

This hologram lens has dependence on the polarization characteristic of incident light. That is, among the incident light of the hologram lens, the S polarization component mainly diffracts, and the diffraction efficiency of the P polarization component becomes lower than this.

This is a strict analysis of the coupled-wave theory (MG Moharam and TK Gayload: Rigourous Coupled-wave theory analysis of planar grating diffraction, J. Opt. Soc. Am. 71,811-818 (1997), MG Moharam and TK Gayload: Rigidous Coupled-wave theory analysis of grating diffraction E-mode polarization and lossws, J. Opt. Soc. Am. 73,451-455 (1893)), for example in the case of reflective thick holograms. In the case where the value (t / Λ) determined by the thickness t of the hologram and the pitch Λ of the interference height in the hologram is 1 to 5, diffraction of TE (S polarization) and TM (P polarization) There is a difference in efficiency, and it is described that the diffraction efficiency of S-polarized light is up to 45% larger than the diffraction efficiency of P-polarized light.

By this phenomenon, the light of the S-polarized component is mainly diffracted in the read light R _L which is obliquely incident on the hologram color filters 124r, 124g, and 124b in this lighting apparatus. Since the light (P polarization component) P _L reflected by the deflection direction by 90 ° is reflected among the illumination light incident almost perpendicularly to the liquid crystal panel 122, since the diffraction effect is low, a lot of light is transmitted to the hologram color filter ( 124r, 124g and 124b are not subjected to diffraction, and are emitted vertically from the hologram color filters 124r, 124g and 124b.

As a typical example of the incident polarization characteristics of the diffraction efficiency of the transmission volume hologram, in the case of refractive index modulation degree 0.04, thickness 3 占 퐉, incident angle 60 °, exit angle 0 °, manufacturing wavelength and reproduction wavelength 532 nm in the hologram medium, As shown in FIG. 5, while the diffraction efficiency of S polarized light _SP becomes 70%, the diffraction efficiency of P polarized light P _P becomes 25%, and the dependence of the diffraction efficiency due to incident polarization appears. do.

As shown in Fig. 6, since the transmittance is improved by increasing the aperture ratio of the external appearance of the transmissive liquid crystal image display element, a transmissive liquid crystal image display element using the refractive microlens array 137 has been proposed.

In this transmissive liquid crystal image display element, illumination light incident on the incident side polarizing plate 135 and linearly polarized by the incident side polarizing plate 135 is incident from the incident side glass substrate 136, and the microlens array 137 By passing through the liquid crystal layer 138, the light is collected on the pixel opening 139 of the TFT. The incident light modulates the polarization state in the pixel opening 139 and is emitted to the output side glass substrate 140. This illumination light then passes through the emission-side polarizing plate 141 and converts the modulation of the polarization state into luminance modulation in this emission-side polarizing plate 141.

In the transmission hologram as described above, the diffraction receiving angle of the incident light is narrow and the diffraction receiving angle and the exit angle are not sufficiently separated, so the light utilization efficiency is low.

In the image display element using the above-mentioned transmission hologram as the color filter, color separation is performed by using the wavelength dispersion of the hologram, so there is no freedom in setting the separation angle of each color light, and color pixels of the color filter and the spatial light modulation element. It is not possible to optimally set the distance between and from the viewpoint of manufacturing difficulty and light utilization efficiency.

In the image display apparatus using this image display element, when the spatial light modulator of the same pixel pitch is assumed, it is not possible to increase the separation angle of each color light, so that the color pixels of the color filter and the spatial light modulator are different from each other. It is not possible to set the distance between to near distances, for example, 50 micrometers or less. That is, in this image display device, it is not possible to improve the light utilization efficiency by widening the wide angle of view and widening of the illumination light to the color filter, and it is not possible to obtain a bright image.

An object of the present invention is to provide a novel transmissive stacked hologram optical element capable of solving the problems of conventional image display apparatuses and an image display apparatus using the optical element.

Another object of the present invention is to widen the diffraction receiving angle of incident light, increase the light utilization efficiency, and to optimally set the distance between the color pixels of the spatial light modulator in terms of manufacturing difficulty and light utilization efficiency. It is to provide a possible transmissive stacked holographic optical element.

A further object of the present invention is to provide an image display element and an image display apparatus capable of displaying a bright image by using a transmissive stacked holographic optical element that can achieve the above object.                 

In order to achieve the above object, the transmissive stacked holographic optical device according to the present invention is a transmissive stacked holographic optical device configured by stacking a plurality of transmissive holographic optical devices having different diffraction incident incidence angles. The emission angle with respect to the center incidence angle of each diffraction receiving incidence angle is different at any wavelength in the visible region.

An image display device according to the present invention comprises a transmissive stacked hologram optical element and a spatial light modulator for modulating the outgoing light from the transmissive stacked hologram optical element, wherein the transmissive stacked hologram optical element has a diffraction receiving incidence angle to each other. A plurality of transmissive holographic optical elements that are different and have different emission angles with respect to the center incidence angle of each diffraction receiving incidence angle at arbitrary wavelengths in the visible region are stacked.

An image display element according to the present invention includes an illumination light source for emitting illumination light, a transmission type hologram optical element diffracting incident light, an illumination optical system for guiding the illumination light to incident light into the transmission type hologram optical element, and the transmission type hologram optical And a spatial light modulator for modulating the illumination light emitted from the device, and an enlarged optical system for enlarging and imaging the illumination light modulated by the spatial light modulator, wherein the transmissive multilayer holographic optical device has different diffraction incident angles and is visible. A plurality of transmissive holographic optical elements having different emission angles with respect to the center incidence angle of each diffraction receiving incidence angle at an arbitrary wavelength of the region are configured.

In the image display device according to the present invention, an illumination light source for emitting illumination light and a plurality of transmissive holographic optical elements having different diffraction incident angles having a structure in which two regions having different incidence polarization orientation dependencies of diffraction ratios are sequentially arranged are stacked. 30 degrees or more with respect to the normal of the illumination light receiving surface of this transmission type polarization selective hologram optical element for said transmission type polarization selective hologram optical element which induces the said illumination light, and said illumination light which diffracts incident light; An illumination optical system incident at an angle of incidence of less than 90 °, a reflective spatial light modulator for modulating the polarization state of the illumination light diffracted by the transmission polarization selective hologram optical element, and a display modulated by the reflective spatial light modulator A magnification optical system for enlarging an image, the transmission polarization selective hole Each transmission hologram optical element constituting the RAM optical element has a different output angle with respect to the center incidence angle of each diffraction receiving incidence angle at an arbitrary wavelength in the visible region, and the P polarization component or S polarization component of the received illumination light is different. While diffracted mainly toward the reflective spatial light modulator, the illumination light which is phase-modulated and re-entered by the reflective spatial light modulator, for the polarization component orthogonal to the polarization component that is mainly diffracted in the first incident When the diffraction efficiency is 10% or less, 70% or more of the above components are transmitted.

A further advantage of the present invention is that the specific advantages obtained by the present invention become clearer from the description of the embodiments described below with reference to the drawings.

1 is a plan view showing an example of a conventional image display apparatus.

2 is a longitudinal sectional view showing another example of a conventional image display element.                 

3 is a graph showing the wavelength dependence of the diffraction efficiency of the hologram optical element used in the conventional image display element.

4 is a longitudinal sectional view showing still another example of the conventional image display element.

Fig. 5 is a graph showing wavelength dependence of diffraction efficiency of a transmission volume hologram used in a conventional image display element.

6 is a longitudinal sectional view showing a conventional image display element using a microlens array.

Fig. 7 is a longitudinal sectional view showing the structure of a transmissive polarization selective hologram optical element constituting the transmissive stacked hologram optical element according to the present invention.

8 is a longitudinal sectional view showing the first embodiment of the transmissive stacked hologram optical element according to the present invention.

Fig. 9 is a graph showing the incidence angle dependence of the diffraction efficiency of each transmission polarization selective hologram constituting the transmission multilayer hologram optical element.

Fig. 10 is a graph showing the emission angle dependence of the diffraction efficiency of each transmission polarization selective hologram constituting the transmission multilayer hologram optical element.

11 is a longitudinal sectional view showing a configuration of a first embodiment of an image display element according to the present invention.

12 is a longitudinal sectional view showing a configuration in which a condensing function is added to a transmissive polarization selective hologram in an image display element.

Fig. 13 is a longitudinal sectional view showing the arrangement of a second embodiment of an image display element according to the present invention.

14 is a longitudinal sectional view showing the configuration of a third embodiment of an image display element according to the present invention.

Fig. 15 is a longitudinal sectional view showing the arrangement of the fourth embodiment of the image display element according to the present invention.

Fig. 16 is a longitudinal sectional view showing the arrangement of the fifth embodiment of the image display element according to the present invention.

17 is a plan view showing the configuration of a first embodiment of an image display device according to the present invention.

18 is a plan view showing the configuration of a second embodiment of an image display device according to the present invention.

Fig. 19 is a front view showing the pixel configuration of the blue and green reflective liquid crystal elements in the image display device.

20 is a front view showing the pixel configuration of a red reflective liquid crystal element in the image display device.

21 is a plan view showing the configuration of a third embodiment of an image display device according to the present invention.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described in detail with reference to drawings.

[1] polarization selective hologram optics                 

First, the structure of the transmission type polarization selective hologram optical element (hereinafter referred to as holographic PDLC) 1 and its manufacturing process used in the present invention will be described with reference to FIG.

In order to manufacture the holographic PDLC used in the present invention, first, a PDLC in which a polymer (hereinafter referred to as a prepolymer), a nematic liquid crystal, an initiator, a dye, and the like is mixed with a glass substrate (2, 3) before photopolymerization occurs Insert in between. At this time, the weight ratio of the nematic liquid crystal is about 40% of the total. The layer thickness (hereinafter, referred to as a cell cap) of the PDLC selects an optimum value in accordance with the specification of the polarization selective hologram optical element in the range of 3 µm to 15 µm.

Next, in order to record the interference height on the holographic PDLC panel 1, the object light 4 and the reference light 5 are irradiated to the holographic PDLC panel 1 from a laser light source (not shown), and the Generates strength and weakness (A). At this time, in the place where the interference height is bright, that is, in the place where the energy of photons is large, the prepolymer in PDLC causes polymerization and polymerizes by the energy. Therefore, the prepolymer is gradually supplied from the periphery, and as a result, the polymerized prepolymer is separated into a dense region and a dense region. In the region where the prepolymer is dense, the concentration of the nematic liquid crystal becomes high. Thus, two regions of the polymer high density region 6 and the liquid crystal high density region 7 are formed. In the case of this embodiment, since the object light 4 and the reference light 5 are irradiated from the same side with respect to the holographic PDLC panel 1, the manufactured holographic PDLC panel 1 becomes a transmission type.

The high polymer density region 6 of the holographic PDLC panel 1 thus produced is isotropic with respect to the refractive index, and the value thereof is, for example, 1.5. On the other hand, in the liquid crystal high density region 7, the nematic liquid crystal molecules are arranged almost perpendicular to the interface with the polymer high density region 6 in the major axis direction. Therefore, in this liquid crystal high density region 7, the refractive index has incident polarization orientation dependence. In this case, the image polarization is an S-polarized component when the reproduction light 9 incident on the light incident surface 8 of the holographic PDLC panel 1 is considered.

The refractive index nlo of the liquid crystal high density region 7 is approximately equal to the refractive index np of the polymer high density region 6, for example, when the refractive index difference is 0.01 or less, the refractive index with respect to the incident S polarization component Since the modulation of is extremely small, diffraction hardly occurs. Generally, the difference (Δn) between the normal ray refractive index nlo and the abnormal ray refractive index nle of the nematic liquid crystal is about 0.1 to 0.2. Therefore, for the regenerated light 9 having the same incident direction, for the P polarized light component, there is a difference in refractive index between the polymer high density region 6 and the liquid crystal high density region 7, and this holographic PDLC panel 1 Silver functions as a phase modulation hologram and generates a diffraction effect.

This is the operation principle of the transmission type polarization selective hologram optical element using holographic PDLC.

[2] a transmissive multilayer hologram optical element according to the present invention

As shown in FIG. 8, the transmissive stacked hologram optical element according to the present invention is disposed between the two sides by the glass substrates 11 and 12, and between the glass substrates 11 and 12. The third transmissive polarization selective holograms 13, 14 and 15 have a structure in which three layers are laminated through barrier layers 16 and 17 between each other.

Fig. 9 shows the incidence angle dependence of the diffraction efficiency when the reproduction wavelength [lambda] play of the transmission polarization selective holograms 13, 14 and 15 is 532 nm. Here, the specifications common to all the transmissive polarization selective holograms 13, 14, and 15 are that the thickness t of the hologram layer is 5 µm, the refractive index modulation degree Δn is 0.05, and the exposure wavelength λrec is 532 nm. .

Incident angles of the object light and the reference light at the time of exposure differ for each transmission polarization selective hologram 13, 14, 15, respectively. Specifically, for the first transmission polarization selective hologram 13 on the incidence side, the reference light incidence angle = 38 °, the object light incident angle = -11 °, and for the second transmission polarization selective hologram 14 in the middle, the reference light. For the incident angle = 47 °, the object light incident angle = 0 °, and the third transmission polarization selective hologram 15 on the exit side, the reference light incident angle = 58 ° and the object light incident angle = 13 °.

Therefore, each transmission-type polarization selective hologram 13, 14, 15 has a different center value of the diffraction receiving angle that satisfies Bragg conditions by about 10 °, and moreover, the emission angles of the emitted light from these three holograms. The center value of is also different by 12 °.

Therefore, the transmissive stacked hologram optical element 10 shown in Fig. 8 has a wide diffraction receiving angle, and each diffracted light A, B, C from each transmissive polarization selective hologram 13, 14, 15 at that time. The dependence of the emission angle of the diffraction efficiency on the back side is smaller than that of the diffraction receiving angle range, as shown in FIG. That is, as can be seen by comparing Figs. 9 and 10, the emission angle ranges of the transmission polarization selective holograms 13, 14, and 15 are smaller than the diffraction receiving angle range.

This is because the angle of incidence of the transmission-type stacked hologram optical element 10 according to the present invention is smaller than the emission angle, whereby the transmission-type laminated hologram is characterized in that the diffraction receiving angle is large but the emission angle after diffraction is small. An optical element has been realized. Therefore, the angle of view of the outgoing light is not excessively increased compared to the incident angle of view, and the second and third transmission polarization selective holograms 14 and 15 of the outgoing light of the first and second transmission polarization selective holograms 13 and 14 are not provided. It is possible to suppress the re-diffraction caused by it.

[3] Image display device according to the present invention

Next, the reflective display device according to the present invention using the above-described holographic PDLC (polarization selective hologram optical element) will be described with reference to FIG.

As shown in Fig. 11, the image display element optically uses the above-described holographic PDLC 10 with respect to the reflective vertical alignment liquid crystal element 18 through a glass substrate 19 having a thickness of about 50 mu m. It is comprised in close contact. In this embodiment, the holographic PDLC 10 corresponds to the transmissive stacked hologram optical element shown in FIG.

The image display element is characterized in that the incident light 21 composed of three incident lights 22, 23 and 24 including both the P-polarized component and the S-polarized component includes incident angles θ1 ± α, θ2 ± β, and θ3 ± γ. ) Is incident from the glass substrate 11 of the holographic PDLC 10. Here, α, β, and γ represent the diffusion angles of the three incident lights 22, 23, and 24.

The incident light first enters the first transmission polarization selective hologram 13. Here, only the P-polarized light of the incident angle (θ3 ± γ) in the diffraction receiving angle of the first transmission polarization selective hologram 13 is diffracted, resulting in the diffracted light 25. The diffracted light 25 proceeds in the direction of the incident angle [theta] 3 '+ [gamma]' with respect to the reflecting surface 20 of the reflective vertical alignment liquid crystal element 18. As shown in FIG.

At this time, as described above, γ <γ 'is satisfied. Since the diffracted light 25 is different from the diffraction receiving angles of the second transmission polarization selective hologram 14 and the third transmission polarization selective hologram 15, the diffraction light 25 is not diffracted once again in the middle of the reflection type and is vertically reflected. The reflection surface 20 is reached via the liquid crystal layer 33 of the liquid crystal element 18.

The diffracted light 25 controls the phase state between the liquid crystal layer 33 and the reciprocating, and when the white display, the polarization direction is rotated by 90 degrees, the polarization state at the time of incidence is preserved when the black display. The modulated light modulated and reflected by the liquid crystal layer 33 and the reflecting surface 20 in this way is reincident to the respective transmission type polarization selective holograms 13, 14, and 15.

When the modulated light is reincident to each of the transmissive polarization selective holograms 13, 14 and 15, the component entering into the diffraction receiving angle range by P polarization and of each of the transmissive polarization selective holograms 13, 14 and 15, It is diffracted again and returns to the opposite direction of the incident light 22, 23, 24. The remaining components that are not diffracted among the P-polarized light and the S-polarized light of the modulated light are not diffracted in the transmission polarization selective holograms 13, 14, and 15, and the light emitted from the holographic PDLC 10 (29). Exit

Similarly to the incident light 23 and 24, the difference α 'and β' of the exit angles are smaller than the incident angle differences α and β.

That is, the second transmission polarization selective hologram 14 diffracts only P-polarized light having an incident angle (Θ2 ± β) within the diffraction receiving angle of the second transmission polarization selective hologram 14 among the incident light. ). The diffracted light 26 travels in the direction of the incident angle θ2 '± β' with respect to the reflecting surface 20 of the reflective vertically aligned liquid crystal element 18. Here, β <β 'is satisfied. Since the diffracted light 26 is different from the third transmissive polarization selective hologram 15, it is not diffracted again on the way, but via the liquid crystal layer 33 of the reflective vertical alignment liquid crystal element 18. The reflective surface 20 is reached. The diffracted light 26 is modulated by the liquid crystal layer 33 and the reflecting surface 20 to re-inject into modulated polarization selective holograms 13, 14, and 15.

Of the modulated light, the P polarized light and the components falling within the diffraction receiving angle range of each of the transmission polarization selective holograms 13, 14, and 15 are diffracted again and are returned to the opposite directions of the incident light 22, 23, and 24. The remaining components that are not diffracted among the P-polarized light and the S-polarized component of the modulated light are not diffracted in the transmission polarization selective holograms 13, 14, and 15, and the light emitted from the holographic PDLC 10 is emitted 30. Exit

In the third transmission type polarization selective hologram 15, only P-polarized light having an incident angle (Θ1 ± α) within the diffraction receiving angle of the third transmission type polarization selective hologram 15 is diffracted, and the diffracted light 27 Becomes The diffracted light 27 travels in the direction of the incident angle θ1 '± α' with respect to the reflective surface 20 of the reflective vertically aligned liquid crystal element 18. Here, α <α 'is satisfied. The diffracted light 27 is modulated by the liquid crystal layer 33 and the reflecting surface 20, and the modulated light is reincident to each of the transmissive polarization selective holograms 13, 14, and 15.

Of the modulated light, the P polarized light and the components falling within the diffraction receiving angle range of each of the transmission polarization selective holograms 13, 14, and 15 are diffracted again and are returned to the opposite directions of the incident light 22, 23, and 24. The remaining components that are not diffracted among the P-polarized light of the modulated light and the S-polarized light component are not diffracted in the transmission polarization selective holograms 13, 14, and 15, and are emitted from the holographic PDLC 10. Exit

On the other hand, the holographic PDLC 10 shown here has a light condensing function, and as shown in FIG. 12, the incident light 21 is directed toward the reflecting surface 20 of the reflective vertically aligned liquid crystal element 18. Condensing That is, in this case, the pitch of the interference height of each of the transmissive polarization selective holograms 13, 14, and 15 of the holographic PDLC 10 is moved from the center 0 to the periphery in the direction of the arrow A shown in FIG. Thinner.

In actual image display, since the liquid crystal layer 33 of the reflection type vertically aligned liquid crystal element 18 is controlled for each pixel, and the polarization state of the reflected light is modulated, the reflected light 32 mainly having S polarization component is used. Image display becomes possible.

Here, [thick hologram] is demonstrated. [Thick hologram] here means that the Q value represented by the following formula becomes 10 or more.

Q = 2πλt / (nΛΛ)

Is the reproduction wavelength, t is the thickness of the hologram layer, n is the average refractive index of the hologram layer, and Λ is the pitch of the interference height.

Moreover, the relationship represented by the following formula holds.                 

Λ = λc / λ ㅣ 2sin {Θs-Θr) / 2} ㅣ

Here, λc is the manufacturing wavelength, Θs is the angle of incidence of the object light, Θr is the angle of incidence of the reference light.

For example, if λc is 0.532 μm, Θs is 40 °, Θr is 0 °, λ is 0.532 μm, t is 8 μm, and n is 1.5, the pitch Λ of the interference height is 0.68 μm and Q is 28.9. , Which fits the definition of [thick hologram] described above.

[Thick hologram] has a high diffraction efficiency, but has a characteristic that the diffraction efficiency decreases relatively rapidly if the reproduction light conditions are different from the conditions of the use wavelengths and the incident angles of the object light and the reference light during manufacture. That is, in any reproduction wavelength, the diffraction efficiency does not appear if the incident angle of the reproduction light differs greatly from the incident angle to which the pitch of diffraction efficiency is given. Therefore, as described above, even if the reflected light 32 becomes a P polarization component, for example, it becomes difficult to diffract in each of the transmission polarization selective holograms 13, 14, and 15.

The polarization selective hologram optical element according to the present invention reduces the pitch Λ of the interference height for the purpose of high diffraction efficiency, so that the band angle, i.e., | Θ -Θr, is set to 30 ° or more.

Next, a second embodiment of the reflection type image display element according to the present invention using the above-described holographic PDLC (polarization selective hologram optical element) will be described with reference to FIG. 7. In this embodiment, as shown in FIG. 13, the transmissive stacked hologram optical element 36 includes a blue light hologram layer 34 provided between the glass substrates 81 and 82, and a glass substrate 82; It has a laminated structure of two layers of the green light hologram layer 35 provided between them, and is integrally formed with the reflection liquid crystal element 37 for blue and green light.

This image display element causes blue light A and green light B to be incident at different incident angles. The blue light hologram layer 34 and the green light hologram layer 35 have different diffraction receiving angles.

The blue light diffracted in the blue light hologram layer 34 is reflected by the lens (cylindrical lens) having a focusing force only in one direction of the blue light hologram layer 34. Is condensed on the blue pixel electrode 38.

The green light diffracted in the green light hologram layer 35 is reflected by the lens (cylindrical lens) having a focusing force only in one direction of the green light hologram layer 35. Light is collected on the pixel electrode 39 for green light. In the blue and green reflective liquid crystal element 37, the liquid crystal layer 85 is provided between the glass substrates 83 and 84, and the color pixel electrodes 38 and 39 are provided on the glass substrate 84 side. It is configured by.

The center of each color hologram layer 34, 35 as a hologram lens almost coincides with the center of the corresponding color pixel electrodes 38, 39. FIG. Since the emission angles from the color hologram layers 34 and 35 are not equal to each other, as shown in Fig. 13, two color lights intersect and are focused.

Illumination light A and B which are color-separated and condensed to each color pixel electrode 38 and 39 are reflected in [white] in an incident polarization direction by 90 degree rotation to S polarized light. Since the reflected light does not deviate from the diffraction receiving angles of the blue light hologram layer 34 and the green light hologram layer 35, the diffraction efficiency is low even with P polarized light, and in each of the color hologram layers 34 and 35, It is not diffracted and is emitted at an angle opposite to each other in the vertical direction of the blue and green reflective liquid crystal elements 37.

Next, a third embodiment of the image display element according to the present invention will be described with reference to FIG.

As shown in Fig. 14, this image display element has a second incident angle receiving range different from each other for the blue light hologram layer 34 and the green light hologram layer 35, and a corresponding emission angle is different. The blue light hologram layer 40 and the second green light hologram layer 41 are added to accommodate the incident angle as indicated by the illumination light (A) to (A) 'and (B) to (B)'. It is possible to widen the range and to improve the light utilization efficiency.

Next, a fourth embodiment of the image display element according to the present invention is shown in FIG. As shown in FIG. 15, the image display element shown in FIG. 15 is configured to separate and collect white illumination light into three colors of red light, green light and blue light by holographic PDLC (polarization selective hologram optical element). . This holographic PDLC has three layers of hologram layers 34 and 35 for green light diffraction, blue light diffraction and red light diffraction, which have different diffraction angles and corresponding emission angles, similar to the two-color separation holographic PDLC described above. And 42 are laminated via barrier layers 16 and 17 between each other. This holographic PDLC is configured such that the holographic PDLC is optically in close contact with the reflective vertical alignment liquid crystal element 18 via a glass substrate 19 having a thickness of about 50 mu m.

In this image display element, the light emitted from the green light diffraction and the blue light diffraction hologram layers 34 and 35 positioned on the incident surface F side is the blue light diffraction and red light located on the emission surface H side. The diffractive hologram layers 35 and 42 condense the three color lights to cross each other so as not to be re-diffracted as much as possible. Green light, blue light, and red light are collected and reflected on the color pixels corresponding to the reflective vertical alignment liquid crystal element 18, respectively.

A fifth embodiment of the image display device according to the present invention, in which the illumination light incident angle of view is improved, instead of the conventional microlens array used for the transmissive liquid crystal image display device, will be described with reference to FIG.

Here, for convenience, the illumination light of any color light of R, G, and B is considered to be divided into illumination light A and illumination light B by the incident angle. The illumination light A and the illumination light B are illumination lights having an angular range of ± Δ ΘA and ± Δ ΘB around the incident angles ΘA and ΘB of 30 ° or more, respectively, and have a relationship of ΘA + ΔΘA = ΘB-ΔΘB. .

Illumination light incident from the incident side glass substrate 43 first enters the first hologram lens array 44. At this time, the first hologram lens array 44 mainly has a diffraction receiving angle corresponding to the incident angle of the illumination light A, and mainly diffracts the illumination light A. FIG. The diffracted light is provided with a barrier layer 45, a second hologram lens array 46, and a glass substrate with a counter electrode for each illumination light having a variable pixel pitch size on the first hologram lens array 44. And light passing through the liquid crystal layer 48 and condensing in the area of the TFT opening 50.

In the second hologram lens array 46 arranged through the barrier layer 45, the illumination light B is mainly diffracted for the same reason. Here too, the barrier layer 45, the second hologram lens array 46, the glass substrate with counter electrode 47 and the liquid crystal for each illumination light having one side pixel pitch size on the second hologram lens array 46 It penetrates the layer 48 and condenses in the area of the TFT opening 50.

  That is, the illumination light is condensed by the two micro lenses of the 1st hologram lens array 44 and the 2nd hologram lens array 46 with respect to one TFT opening part 50. Since the first and second hologram lens arrays 44 and 46 vibrate as independent micro lens arrays, respectively, it is possible to secure a large receiving angle as compared with a normal refractive system micro lens array.

The first hologram lens array 44 and the second hologram lens array 46 used herein do not include a material having refractive index anisotropy, and thus do not have great polarization selectivity.

[4] an image display apparatus according to the present invention

As the image display apparatus according to the present invention, the configuration and operation principle of a three-plate projection type image display apparatus using three reflective liquid crystal elements for the image display element and two dichroic mirrors as the color separation composition means, It demonstrates with reference to FIG.

The image display apparatus enters into the illumination optical system 52 which has the functions of the luminous flux emitted from the UHP lamp light source 51 having the functions of correcting the cross-sectional shape of the beam, uniformizing the intensity distribution, controlling the divergence angle, and the like. This illumination optical system 52 includes a P-S polarization converter. This P-S converter is polarization converting means having a function of equipping an unpolarized incident light beam with polarization of either P-polarized light or S-polarized light with an efficiency of 50% or more. In the case of this embodiment, the light beam transmitted through the illumination optical system 52 is mainly a polarization state in which the electric vector vibrates in the direction parallel to the surface of FIG. 17, that is, P polarization for the next incident mirror 53. It is converted to be light.

The illumination light is reflected by the mirror 53 and enters the dichroic mirror 54 of red reflection. In this dichroic mirror 54, mainly red light is reflected toward the spatial light modulator 55 for red light. In the red-light spatial light modulator 55, red light is incident at an incident angle of about 50 ° ± 15 °.

On the other hand, the blue and green light having passed through the dichroic mirror 54 of red reflection enters the dichroic mirror 56 for reflecting blue light. In this blue light reflection dichroic mirror 56, only blue light is reflected toward the blue light spatial light modulator 57. Blue light is incident on the blue light spatial light modulator 57 at an incident angle of about 50 ° ± 15 °.
The green light transmitted through the dichroic mirror 56 for reflecting blue light is incident on the green light spatial light modulator 58 at an incident angle of about 50 ° ± 15 °.

On the optical path from the blue light reflecting dichroic mirror 56 to the green light spatial light modulator 58, the orange cut filter 59 reflecting the spectrum on the wavelength side longer than the wavelength around 570 nm is detached. It is arrange | positioned as possible. The orange cut filter 59 is inserted in the optical path in order to improve the color reproducibility of the display image. When brightness is given priority over color reproducibility, by placing the orange cut filter 59 outside the optical path, the orange color light in the vicinity of 580 nm included in the illumination light from the UHP lamp light source 51 is used as the spatial light modulator for green light. (58), it contributes to the image formation of the displayed image.

The spatial light modulator 58 for green light, the spatial light modulator 57 for blue light, and the spatial light modulator 55 for red light are respectively shown in the first embodiment of the above-described image display device. And the polarization-selective stacked hologram optical elements 58a, 57a, 55a and the reflective spatial light modulators 58b, 57b, 55b. Therefore, the green light, blue light, and red light having mainly P polarization components incident on the green light spatial light modulator 58, the blue light spatial light modulator 57, and the red light spatial light modulator 55 are respectively P. Only the polarization component is diffracted and is incident on each reflective spatial light modulator 58b, 57b, 55b at an incident angle of ± 10 °. Such green light, blue light, and red light modulate the polarization state for each pixel of each of the reflective spatial light modulators 58b, 57b, and 55b, and then once again at a polarization-selective stacked hologram optical element at an emission angle of ± 15 °. It is emitted to air from 58a, 57a, 55a.

On the other hand, the thickness of each liquid crystal layer of the reflective spatial light modulators 58b, 57b, 55b is optimized in response to the difference in the color light to be modulated respectively.

The spatial light modulator 58 for green light and the spatial light modulator 55 for red light are arrange | positioned with respect to the dichroic mirror 54 of red reflection. The blue light spatial light modulator 57 and the green light spatial light modulator 58 are arranged at a position in conjugate with respect to the dichroic mirror 56 of blue reflection.

Therefore, the illumination light of each color light modulated by the blue light spatial light modulator 57, the green light spatial light modulator 58, and the red light spatial light modulator 55 is a dichroic mirror of blue reflection ( 56, again synthesized by the dichroic mirror 54 of red reflection. This illumination light enters the projection optical system 61 via the polarization selection means 60 for S-polarization transmission, like a polarizing plate, for example. The projection optical system 61 forms an incident illumination light on a screen (not shown). An image is displayed on the screen.

On the other hand, the dichroic mirror 56 of blue reflection and the dichroic mirror 54 of red reflection may be made with the thin film characteristic of the part which performs color separation and the thin film characteristic of the part which carries out color synthesis different.

Next, FIG. 18 shows a second embodiment of the image display device according to the present invention. As shown in Fig. 18, the image display apparatus uses the dichroic mirror 64 as the color synthesizing means by using the reflective liquid crystal elements 62 and 63 as the image display elements, and the two reflective types. Polarization-selective stacked holographic optical element as color separation condensing means for one reflective liquid crystal element 62, using dichroic mirrors 65, 66, 67 as color separation means for liquid crystal elements 62, 63 The configuration and operation principle of a two-panel projection type image display apparatus using 62a will be described.

The luminous flux emitted from the UHP lamp light source 51 enters into the illumination optical system 52 having functions such as correction of the luminous flux cross-sectional shape, uniformity of light intensity distribution, divergence angle control, and the like. The illumination optical system 52 includes a P-S polarization converter 68. This P-S converter 68 is a polarization conversion means having a function of equipping a non-polarized light beam with P polarized light or S polarized light with an efficiency of 50% or more. In the case of this embodiment, the light beam transmitted through the illumination optical system 52 is mainly a polarized state in which the electric vector vibrates in a direction parallel to the surface of FIG. Is converted to be P-polarized light.

The illumination light reflects the green light component and the blue light component in the dichroic mirror 65 of the green reflection and the dichroic mirror 66 of the blue reflection, and reflects the green and blue reflective display elements at different angles. Enters 62). The incident angle of blue light is about 45 degrees. The incident angle of green light is about 55 degrees.

Illumination light transmitted through the dichroic mirror 65 of green reflection and the dichroic mirror 66 of blue reflection is reflected by the dichroic mirror 67 of red reflection through the condenser lens 69, Incident on the red reflective display element 63 at an incident angle of about 45 °.

The green and blue reflective display elements 62 used by this embodiment are the same as those described by the third embodiment of the image display element, and blue and green light are respectively assigned to the corresponding color pixels. A polarization-selective stacked hologram optical element 62a having a plurality of hologram layers for condensing, and a reflective liquid crystal element 62b having two color pixels for blue and green are provided in close contact with each other.

The red reflective display element 63 corresponds to the above-mentioned transmissive liquid crystal element of the image display element in place of the reflective liquid crystal element, and has a polarization-selective stacked type having a plurality of hologram layers that focus on color pixels corresponding to red light. The hologram optical element 63a and the reflection type liquid crystal element 63b having the color pixel for red are in optically close contact with each other.

The illumination light mainly composed of P polarization components incident on the reflective display elements 62 and 63 modulates the polarization state for each pixel, and the polarization state is modulated by the respective reflective display elements 62 and 63. Is reflected from. The P polarization component is diffracted and deflected when it is incident again on the polarization selective stacked hologram optical element 62a. The S-polarized component is not diffracted even when it is incident again on the polarization selective stacked hologram optical elements 62a and 63a, and passes through the polarization selective stacked hologram optical elements 62a and 63a.

The two modulated lights composed of the S-polarized component transmitted through the polarization-selective stacked holographic optical elements 62a and 63a are color synthesized by the dichroic mirror 64 and then passed through the polarizing plate 60 of the S-polarized light transmission. And enters the projection optical system 61. The projection optical system 61 forms an incident illumination light on a screen (not shown). An image is displayed on the screen.

The blue and green reflective liquid crystal element 62b has a pixel structure in which the green pixel G and the blue pixel B are alternately arranged, as shown in FIG. As shown in FIG. 20, the red reflective liquid crystal element 63b is composed of only the red pixel R, and has the same pixel structure as the blue and green reflective liquid crystal element 62b. In this red reflective liquid crystal element 63b, two basic pixels are equally driven as one pixel.

On the other hand, in the reflective spatial light modulators 62 and 63, the thickness of each liquid crystal layer is optimized according to the difference in the color light to be modulated respectively.

Next, FIG. 21 shows a third embodiment of the image display device according to the present invention.

The image display apparatus shown in FIG. 21 is a single-plate projection image display apparatus, and uses a polarization selective stacked holographic optical element as color separation condensing means for the reflective liquid crystal element 18. As shown in FIG. In this apparatus, the illumination light beam emitted by the UHP lamp light source 51 enters into the illumination optical system 52 having functions of correction of the light beam cross-sectional shape, uniformity of light intensity distribution, divergence angle control, and the like. The illumination optical system 52 includes a P-S polarization converter 68. The P-S converter 68 is a polarization conversion means having a function of equipping a non-polarized light beam with P polarized light or S polarized light with an efficiency of 50% or more. In the case of this embodiment, the light beam transmitted through the illumination optical system 52 is mainly a polarization state in which the electric vector vibrates in a direction parallel to the surface of FIG. 15, that is, the dichroic mirrors 66 and 65 which enter next. , P) for 67).

The illumination light reflects the green component, the blue component and the red component in the dichroic mirror 65 of the green reflection, the dichroic mirror 66 of the blue reflection, and the dichroic mirror 67 of the red reflection. , At different angles, enter the reflective display device 72 through the coupling prism 70. The coupling prism 70 is in close optical contact with the reflective display element 72 in order to increase the angle of incidence of the reflective display element 72 into the polarization-selective stacked holographic optical element 73, for example, about 55 °. Is attached.

The reflective display element 72 used in this embodiment is basically the same as that shown in the fourth embodiment of the image display element. The polarization-selective stacked holographic optical element 73 used here is a holographic PDLC optical element, and is intended to diffract P polarized light and not to diffract S polarized light. The holograms 34, 35, and 36 for each color light of R, G, and B have a stacked structure of three layers, and are integrally formed with the reflective liquid crystal element 18. As shown in FIG.

The holograms 34, 35, and 36 for each color light have a function of a cylindrical lens having condensing power in one direction so that the illumination light crosses and condenses on the corresponding basic pixels of the reflective liquid crystal element 18. .

By the holograms 34, 35, and 36 for each color light, the illumination light that is color-separated and condensed on each of the pixel electrodes 74, 75, and 76 of R, G, and B is modulated and reflected by the polarization state. In the reflected light, the S-polarized component is not diffracted when incident again on the holograms 34, 35, 36 for each color light, and is emitted with a constant exit angle with respect to the reflective display element 72.

This reflected light is detected by the polarizing plate 60 of S-polarized light transmission, and is incident on the projection optical system 61. The projection optical system 61 forms an incident illumination light on a screen 71 (not shown). On the screen 71, an image is displayed.

It is to be understood by those skilled in the art that the present invention is not limited to the above-described embodiments described with reference to the drawings, and that various changes, substitutions, or equivalents thereof may be made without departing from the scope and spirit of the appended claims. It is clear.

As described above, the present invention is obtained by stacking a plurality of transmissive holographic optical elements that differ in diffraction receiving angles and differ in emission angle with respect to the center incidence angle of each diffraction receiving incidence angle at any wavelength in the visible region. The transmission multilayer hologram optical element having a wide diffraction receiving angle of incident light is realized.

The image display device according to the present invention is a color image display device having a hologram color filter by combining a transmission type laminated hologram optical device in which each transmission hologram optical element has a function of a microlens array, and a spatial light modulator having a color pixel. It is configured as. Therefore, this image display element has a color filter of an absorption type using a color pixel, a hologram color filter having a single layer structure, or a hologram color filter having diffraction angles and emission angles having a stacked structure that are not sufficiently separated from each other. The image display device has a high light utilization efficiency.

This image display element is used together with a transmissive liquid crystal image display element as a replacement for a conventionally used microlens array even when each transmission hologram optical element does not have a function as a color filter, thereby widening an angle of view for receiving illumination light. In addition, it is possible to constitute an image display element having a high light utilization efficiency.

The image display element includes a plurality of transmissive holographic optical elements having different diffraction angles, wherein only one color light is emitted from the color light of R (red), G (green), and B (blue), respectively, by the diffraction angle. By incidence, color separation without using wavelength dispersion of the hologram is possible.

Thereby, a degree of freedom is obtained for setting the separation angle of each color light, and it is preferable that the distance between the hologram color filter and the color pixel of the spatial light modulator is set at an optimum distance from the viewpoint of manufacturing difficulty and light utilization efficiency. It is possible. In the case of a spatial light modulator having the same pixel pitch, in particular, by increasing the separation angle of each color light, the distance between the hologram color filter and the color pixel of the spatial light modulator is, for example, 50 μm or less. It is possible to set. Further, by widening the angle of view and widening of the illumination light with respect to the hologram color filter, a bright image display device having improved light utilization efficiency can be realized.

By constructing each hologram layer of the transmissive stacked hologram optical element with a polarization selective hologram optical element, a polarization splitting element having a light receiving angle can be realized.

The image display device according to the present invention uses the above-described transmission type stacked hologram optical element and a reflective spatial light modulator to eliminate the need for a PBS (polarizing beam splitter), and is configured as a compact, light weight, high efficiency and low cost image display device. It is.

In this image display apparatus, by adding the color filter function by the microlens array, color synthesizing means is unnecessary, and it is possible to configure as an image display apparatus which is small in size and low in cost.

According to the present invention, the optical diffraction angle of incident light is widened, the light utilization efficiency is increased, and the distance between the color pixels of the spatial light modulator is set at an optimum distance from the viewpoint of manufacturing difficulty and light utilization efficiency. It is possible to provide a transmissive stacked hologram optical element, and it is possible to provide an image display element and an image display apparatus capable of displaying a bright image using the transmissive laminated hologram optical element.

Claims (65)

delete delete delete delete delete delete delete delete A transmission type laminated hologram optical element, And a spatial light modulator for modulating the light emitted from the transmissive stacked hologram optical element, The transmissive multilayer holographic optical element is formed by stacking a plurality of transmissive holographic optical elements having different diffraction incident incidence angles and having different exit angles with respect to the center incidence angle of each diffraction accepting incident angle at arbitrary wavelengths in the visible region. An image display element. The method of claim 9, And wherein each transmission hologram optical element has an emission angle range corresponding to an arbitrary angle range of incidence within the diffraction receiving angle of incidence. The method of claim 9, And each of the transmissive holographic optical elements comprises a polarization-selective holographic optical element having a configuration in which two regions having different incidence polarization orientation dependencies of refractive indices are sequentially arranged. The method of claim 9, Wherein each of said transmissive holographic optical elements comprises a polarization selective holographic optical element comprising a polymer dispersed liquid crystal material. The method of claim 9, Each of said transmissive holographic optical elements has a light condensing function. The method of claim 9, Each of said transmissive holographic optical elements constitutes a microlens array, and focuses illumination light on corresponding pixels of the spatial light modulator. The method of claim 14, And at least one or more sets of chief rays of illumination light condensed from the respective transmissive holographic optical elements to the corresponding pixels of the spatial light modulator. The method of claim 9, And said transmissive holographic optical element constitutes a microlens array and has a color filter function for separating and condensing illumination light on corresponding pixels of the spatial light modulator. The method of claim 16, And at least one or more sets of chief rays of illumination light condensed on the corresponding pixels of the spatial light modulator by the respective transmissive hologram optical elements. The method of claim 9, And the number of stacked hologram optical elements is three or more. The method of claim 9, The transmission laminated holographic optical element is an image display element characterized in that the exit angles to the central incident angle of each diffraction receiving incidence angle are different by at least 5 degrees at any wavelength in the visible region. The method of claim 9, The spatial light modulator is a reflective spatial light modulator, and modulates the illumination light incident by the transmission hologram optical element of the transmission multilayer hologram optical element and injects the light into the transmission hologram optical element again. device. The method of claim 9, And the light modulation surface of the spatial light modulation element is parallel to the hologram surface of the transmissive multilayer hologram optical element. The method of claim 9, And an interval between the hologram surface of the transmissive multilayer hologram optical element and the optical modulation surface of the spatial light modulator is 50 占 퐉 or less. An illumination light source emitting illumination light, A transmission type laminated hologram optical element diffracting incident light, An illumination optical system for guiding the illumination light into incident light on the transmissive stacked hologram optical element; A spatial light modulator for modulating illumination light emitted from the transmissive multilayer holographic optical device; An enlarged optical system configured to enlarge and form an illumination light modulated by the spatial light modulator, The transmissive multilayer holographic optical element is formed by stacking a plurality of transmissive holographic optical elements having different diffraction incident incidence angles and having different exit angles with respect to the center incidence angle of each diffraction accepting incident angle at arbitrary wavelengths in the visible region. An image display apparatus. The method of claim 23, wherein And wherein each transmission hologram optical element has an emission angle range corresponding to an arbitrary angle range of incidence within the diffraction receiving angle of incidence. The method of claim 23, wherein The transmissive holographic optical element has an illumination optical system in which illumination light is incident at an angle of incidence of 30 degrees or more and less than 90 degrees, and the diffraction efficiency of the illumination light that becomes the first polarization direction among the incident illumination lights is 50% or more, The diffraction efficiency of the illumination light of the 2nd polarization direction orthogonal to 1 polarization direction becomes 10% or less, The image display apparatus characterized by the above-mentioned. The method of claim 25, And said first polarization direction is P-polarized light. The method of claim 23, wherein Wherein each of said transmissive hologram optical elements is a polarization selective hologram optical element having a configuration in which two regions having different refractive indices of incident polarization orientations are sequentially arranged. The method of claim 23, wherein Wherein each of said transmissive holographic optical elements is a polarization selective holographic optical element comprising a polymer dispersed liquid crystal material. The method of claim 23, wherein And said transmissive holographic optical element has a light condensing function. The method of claim 23, wherein And said transmissive hologram optical element constitutes a microlens array, and focuses illumination light on corresponding pixels of the spatial light modulator. The method of claim 30, And at least one or more sets of chief rays of illumination light condensed on the corresponding pixels of the spatial light modulator by each of the transmissive holographic optical elements. The method of claim 23, wherein And each of the transmissive holographic optical elements constitutes a microlens array and has a color filter function for separating and condensing illumination light onto corresponding pixels of the spatial light modulator. The method of claim 32, And at least one or more sets of chief rays of each color light of the illumination light condensed on the corresponding pixels of the spatial light modulator by the respective transmissive holographic optical elements. The method of claim 32, And the illumination optical system performs color separation and condensing of the illumination light by injecting different color light of the illumination light into each of the transmission hologram optical elements at a diffraction receiving angle of each transmission hologram optical element. The method of claim 23, wherein And the number of laminated hologram optical elements is three or more. The method of claim 23, wherein The transmission type holographic optical element is an image display apparatus characterized in that the emission angles with respect to the center incidence angle of each diffraction receiving incidence angle are different by at least 5 degrees at any wavelength in the visible region. The method of claim 23, wherein And said spatial light modulator is a reflective spatial light modulator. The method of claim 23, wherein And the light modulation surface of the spatial light modulation element is parallel to the hologram surface of the transmissive stacked hologram optical element. The method of claim 23, wherein And an interval between the hologram surface of the transmissive stacked hologram optical element and the light modulation surface of the spatial light modulator is 50 占 퐉 or less. The method of claim 23, wherein The transmissive multilayer holographic optical element is characterized by injecting chief rays of illumination light at an angle to the spatial light modulator. The method of claim 23, wherein And said illumination optical system has color separation means and injects only a part of the spectrum of illumination light into said transmission type stacked hologram optical element. The method of claim 23, wherein And said illumination optical system has color separation means and injects light of a plurality of wavelength bands in the spectrum of illumination light into at least one transmissive holographic optical element at different incident angles. The method of claim 42, wherein And light in different wavelength bands incident on the transmissive holographic optical element is blue light and green light. The method of claim 42, wherein And light in different wavelength bands incident on the transmissive holographic optical element is blue light and red light. The method of claim 23, wherein And a polarization selecting means in an optical path between the spatial light modulator and the projection optical system. An illumination light source emitting illumination light, A transmissive polarization selective hologram optical element for diffracting incident light, comprising a plurality of transmissive holographic optical elements having different diffraction receiving incident angles having a structure in which two regions having different incidence polarization orientation dependencies of diffraction rates are sequentially arranged; An illumination optical system for inducing the illumination light and injecting the transmission polarization selective hologram optical element at an incident angle of 30 ° or more and less than 90 ° with respect to the normal of the illumination light receiving surface of the transmission polarization selective hologram optical element; A reflective spatial light modulator for modulating the polarization state of the illumination light diffracted by the transmission polarization selective hologram optical element; An enlarged optical system for enlarging a display image modulated by the reflective spatial light modulator, Each transmission hologram optical element constituting the transmission polarization selective hologram optical element has a different emission angle with respect to the center incidence angle of each diffraction receiving incidence at an arbitrary wavelength in the visible region, and a P polarization component of the illumination light received, or The polarized light component diffracted at the first incidence of the illumination light which diffracts the S-polarized light component toward the reflective spatial light modulator and is phase-modulated by the reflective spatial light modulator and re-entered, and the polarized light which is orthogonal The diffraction efficiency with respect to the component is 10% or less, so that 70% or more of the orthogonal polarization component is transmitted. The method of claim 46, And wherein each transmission hologram optical element has an emission angle range corresponding to an arbitrary angle range of incidence within the diffraction receiving angle of incidence. The method of claim 46, The first polarization direction is P polarized light, characterized in that the image display device. The method of claim 46, Wherein each of said transmissive holographic optical elements is a polarization selective holographic optical element comprising a polymer dispersed liquid crystal material. The method of claim 46, Each of said transmissive holographic optical elements has a light condensing function. The method of claim 46, And the number of laminated hologram optical elements is three or more. The method of claim 46, And each of the plurality of transmissive holographic optical elements has an exit angle with respect to the center incidence angle of each diffraction receiving incidence angle at an arbitrary wavelength in a visible region different from each other by 5 degrees or more. The method of claim 46, Wherein each of the transmissive holographic optical elements constitutes a microlens array, and condenses an illumination light on each corresponding pixel of the reflective spatial light modulator. The method of claim 53, And at least one or more sets of chief rays of illumination light condensed from the respective transmissive holographic optical elements to the corresponding pixels of the reflective spatial light modulator, at least one pair or more. The method of claim 46, And each of the transmissive holographic optical elements constitutes a microlens array and has a color filter function for collecting and condensing illumination light onto corresponding color pixels of the reflective spatial light modulator. The method of claim 55, And at least one or more sets of chief rays of illumination light condensed from the respective transmissive hologram optical elements to the corresponding color pixels of the reflective spatial light modulator, at least one or more sets of each other. The method of claim 55, And the illumination optical system performs color separation and condensing of the illumination light by injecting different color light of the illumination light into each of the transmission hologram optical elements at a diffraction receiving angle of each transmission hologram optical element. The method of claim 46, And a hologram surface of said transmissive polarization selective hologram optical element and an optical modulation surface of said reflective spatial light modulator are parallel. The method of claim 46, And an interval between the hologram surface of the transmissive polarization selective hologram optical element and the optical modulation surface of the reflective spatial light modulator is 50 占 퐉 or less. The method of claim 46, And said transmissive polarization-selective hologram optical element injects chief rays of illumination light at an angle to said reflective spatial light modulator. The method of claim 46, And said illumination optical system has color separation means, and injects only a part of the spectrum of illumination light into said transmissive polarization selective hologram optical element. The method of claim 46, And said illumination optical system has color separation means and injects light of a plurality of wavelength bands in the spectrum of illumination light into at least one transmissive holographic optical element at different incident angles. The method of claim 62, And light in different wavelength bands incident on the transmissive holographic optical element is blue light and green light. The method of claim 62, And light in different wavelength bands incident on the transmissive holographic optical element is blue light and red light. The method of claim 46, And a polarization selecting means in an optical path between the reflective spatial light modulator and the projection optical system.

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